The proliferation of competitors within the wireless market has placed increased cost pressures on wireless terminal manufacturers. Thus, increased functionality at reduced cost is a primary driver in wireless component development. This has forced digital technologies to increasingly encroach into analog devices, generally increasing device complexities but also providing opportunities for increased functionality.
A typical wireless terminal platform includes an integrated device performing modem and application layer functions and a radio frequency integrated circuit (RFIC) that performs RF to baseband/IF functions. Communication between the controlling device and the RFIC is typically via a low-bandwidth serial channel. Thus, for recurring communications, such as receive gain control adjustments due to environment changes, it is desirable to limit the amount of information to be transferred.
However, typical RFIC gain is distributed to multiple stages within the receive chain, resulting in a large number of transactions needed to provide gain control. Furthermore, because the gain stages are individually controlled, the partitioning must be calculated by the modem for every change. Because the modem generally has to send a separate gain update to the RFIC for each gain stage, the overall change in the gain of the RFIC is unsettled as the individual changes are transmitted. Also, during this unsettled period, the communications channel is unavailable for other control signals, possibly affecting time critical commands to other channels. For standard applications in which gain updates are performed on the order of every 10 s of microseconds, bandwidth and processing must be minimized. Therefore, there is a need in the art for an improved method of providing gain control in the RFIC.